Traditionally, men taught their sons to channel their energies in acceptable ways. This included learning a trade, being protective of women and children, and preparing to take on their adult roles as husbands and fathers. Women taught their daughters to nurture children and keep the home. Husbands and wives balanced each others' strengths and weaknesses.
What's in vogue today is to teach children that their gender-specific instincts are wrong. Boys are punished for being rambunctious and restless in school. Girls are ridiculed for wanting to embrace the home. Children become confused when their instincts conflict with what they're being taught, either at school, at home, or in society.